The present invention relates to a disk drive, and more particularly to a disk drive that can be simplified in structure and can be reduced in number of parts by making an installation plate, which is mounted on a base, be integrally formed with various functional portions.
A disk drive capable of recording or reproducing an information signal to/from a disk-shaped recording medium such as an optical disk and a magneto-optical disk is provided with an optical pickup. The optical pickup is adapted to be moved in the radial direction of the recording medium mounted on a disk table and to direct laser light onto the recording medium.
Such an optical pickup is provided as a part of a base unit, for example. The base unit has a housing composed of a boxlike base opening to one side and an installation plate for closing the opening of the base. Required components including the optical pickup and the disk table are installed in the housing.
A guide mechanism is required to move the optical pickup in the radial direction of the recording medium. For example, such a guide mechanism includes two parallel guide shafts (see Japanese Patent Laid-open No. Hei 9-198686, for example). The two guide shafts are slidably inserted through two guided portions (bearing portions) provided on a moving base of the optical pickup, whereby the optical pickup is moved in the radial direction of the recording medium as being guided by the two guide shafts.
On the other hand, the disk table for mounting the recording medium thereon is fixed to a motor shaft of a spindle motor and is rotated about the axis of the motor shaft by the spindle motor. The spindle motor includes a rotor and a stator. The rotor is rotated about the axis of the motor shaft relative to the stator.
In general, a disk drive includes a disconnection preventing mechanism for preventing disconnection of the rotor of a spindle motor from the stator due to vibrations generated during transportation or shock upon falling or the like.
FIG. 38 shows such a disconnection preventing mechanism in a conventional disk drive. As shown in FIG. 38, a motor shaft c is fixed to a rotor b of a spindle motor a, and a disk table d is fixed to the motor shaft c. A stator board g of a stator f is provided on a base e, and a disconnection prevention member h is mounted on the stator board g by a mounting screw i.
In this conventional disk drive, however, two dedicated guide shafts are required as a guide mechanism for guiding an optical pickup. Thus, the number of parts is large, and the mechanism is complicated, causing an increase in manufacturing cost.
Further, in assembling the base unit, it is necessary to mount the installation plate on the base e after mounting the two guide shafts and the disconnection prevention member h. Conversely, in performing the maintenance of the base unit, the installation plate is first removed from the base e, and the guide shafts and the disconnection prevention member h are next removed. Thus, the number of man-hours required is large, causing a troublesome work.
If the disconnection prevention member h is formed from a resin material, the manufacturing cost can be reduced. However, in the case of a large vibration or shock, there is a possibility that the disconnection prevention member h may break to impair the function of the disconnection preventing mechanism.